This invention pertains generally to the field of mops and related floor cleaning devices, and more particularly, to mops having an adjustable mop head or frame, so that the size of the mop head may be varied by the mop user to efficiently clean stairs and floors of various configurations having furniture and other obstacles.
Previous mops have been designed with mop heads that are adjustable or collapsible for a variety of different reasons. Some mops have collapsible mop head frames to facilitate removal and replacement of the mop head fabric or swab. Such mops are disclosed, for example, in U.S. Pat. No. 2,192,861 (Burchell), U.S. Pat. No. 2,840,840 (Yamen), and U.S. Pat. No. 3,458,886 (Goettel). These mops have mop head frames that can be folded downward so that the frame is easily removable from pockets in the mop head swab. Other mops are provided with mop head frames of variable length, so that the fabric of the mop head swab can be held taut while the mop is in use and the head can be adjusted to compensate for shrinkage of the fabric after the swab has been washed. Examples of these mops are described in U.S. Pat. No. 2,325,598 (Fatland), U.S. Pat. No. 2,921,327 (Kuehl), and U.S. Pat. No. 3,405,418 (Carter et al.).
The present invention is directed toward mops that are useful for cleaning floor areas of various sizes and shapes, such as stairs, narrow hallways, areas around corners and posts, under chairs and furniture, and large clear areas such as showroom floors, wide corridors, gymnasiums, and the like. Obviously mops having a variable width are useful for these purposes. Such mops have been disclosed in U.S. Pat. No. 2,254,648 (Gilsdorf), U.S. Pat. No. 2,756,453 (Mattson), and U.S. Pat. No. 3,911,521 (Franchot). These mops all have heads of widths that are variable over a very limited range, specifically so that the floor area engaged in a single pass of the mop can be adjusted. This feature is particularly desirable when one is cleaning around and under furniture.
Another mop having a variable mop head width is described in U.S. Pat. No. 2,860,360 (Leavelle). The purpose of the width adjustment in this case is to enable the sweepings to be easily picked up at the end of a pass of the mop by closing the arms of the mop head and trapping the debris in an attached hood. Clearly this objective is different from the purpose of the adjustable-width mops referred to above.
Other mops have been designed with oblong mop heads and handles that can pivot about different axes, so that the effective width of the mop head can be adjusted by rotating the mop about a vertical axis. Examples are disclosed in U.S. Pat. No. 1,989,825 (Schaefer et al.), U.S. Pat. No. 2,724,851 (Steiner), and the Fatland disclosure mentioned above. In fact, mops having a universal-type joint between the handle and mop head are generally known to be useful for cleaning corners, around furniture and obstacles, and other areas that are difficult of access. Such a mop is described in U.S. Pat. No. 3,050,762 (Ballinger).
From the foregoing disclosures it is clear that the problem of designing mops that are useful in confined areas or floors with obstacles has been addressed by others. The solutions have been limited in success. The concept of a universal-type joint between the mop head and the handle has been used to improve the maneuverability of mops with oblong heads, but it doesn't solve the problems arising from the shape or size of the mop head itself. Some of the above mops with heads of adjustable width become deeper in the fore-aft dimension when the width is decreased. This impairs the maneuverability of these mops in many situations. In all cases, the range of head widths is limited and their usefulness is impaired for cleaning large clear floor areas.